Okay I'm not really sure how to explain this one but I'll do the best I can.

If I am running a task that will take a long period of time, like a render in Cinelerra, or a transcode operation with avconv, I will often just let my computer alone and go do something else while it is running; I assume that is a fairly common practice.

I come back a few hours later and the task is done, but now the computer is running very sluggish and laggy. When it gets like this even the smallest of things will max out both cores and take a long time. For example, opening VLC will max both cores and take about 30 seconds just to show the main window. and playing video is skippy.
Opening a Dolphin window takes over a minute and even updating the panel info as the cursor moves over various files takes several seconds.

This only happens after I come back from letting the computer perform a long task, and also this does not happen in Windows so I don't think it is hardware related problem.

I am not sure what info to post to help solve this other than I am running Mint 13 KDE
Here is an lspci:

Jaws When it happened I pressed CTRL+ESC, which along with everything else, took about 30 seconds to load... when it did I clicked the sort-list to arrange everything by CPU usage, and the only things of note were kde4 taking 6% cpu, kwin taking 5%, and python which was listed as a zombie (no idea what that means).

Everything else was zero or 1%

squeezy The machine has 4 Gigs of ram. If it is a memory issue, wouldn't this have also happened on Vista, since Vista is generally considered the most memory-hogging OS ever? Is there a setting I need to tweak or some way to tell for certain?

With 4 GB of RAM it probably isn't memory issue. I don't know how you could check it, maybe see how much of the swap partition is in use?

Is Vista not a memory hog? I was told that it was one of the worst.

Using system monitor, my swap barely is being used at all. But to my amazement, with just system monitor and this one firefox window, almost all of my RAM is being used! 3 Gigs in use! That seems excessive for just the monitor and one firefox window. If that s accurate, then your original theory may be correct.

I guess Vista isn't the worst after all. Clearly I need to thin things out, but I'm not sure how to do that or what is safe to terminate. Any suggestions?EDIT:
According to system monitor, kde4 is using 2.5 Gigs, all by itself! That is rather insane isn't it? Any way to trim that down a bit?--Jim

RJim wrote:Using system monitor, my swap barely is being used at all. But to my amazement, with just system monitor and this one firefox window, almost all of my RAM is being used! 3 Gigs in use!

I assume this the case after you run Cinelerra?

According to system monitor, kde4 is using 2.5 Gigs, all by itself!

I'm not even seeing a kde4 process running on my system. I do have a kded4 though. Are you using desktop effects by any chance?

Also you can right click on a process and see a detail memory info, though you my need to be root for those processes. And yes that seems excessive unless Cinelerra has a memory leak. Memory should be released for new processes that start running.

Jaws, you are correct, it is kded4 that I was referring to, my mistake...

Last night it was after I ran a long avconv operation that I made that post, but today after a fresh reboot, kded4 starts at 100MB usage, and has been growing continually at a rate of 1MB every three seconds! I literally just sat here and watched the memory usage for 2 minutes, and it just kept growing for that process. Right now it is at 180MB and continuing to rise. This seems unusual.

I did some searching last night and found some posts that said to disable Nepomuk, and so I did that, but this is still happening.

Do you see this behavior on your system? Or is my computer jut "special"?

Here are the details from right clicking the process as you suggest. Notice how just between the time of my last post and this one, how it has continued to eat memory.
It is even higher than in the screen shot now.

My kded4 is steady at 22MB but I'm not doing anything memory intensive.

To find any problem it's best to use a process of elimination, but first I'd making sure my system was up to date in Update Manager. I wouldn't be using desktop effects or anything else that might be pulling resources. Keep everything as simple as possible.

I'd then start in System Settings, system administration, startup and shutdown, session management, on login, and select Start with an empty session. Reboot.

I'd then go to service manager in the same Start up and Shutdown dialog and start killing off startup services one by one, checking resource usage as I go along. Rebooting after each one was stopped.

Jaws, I tried what you suggested. Setting the system to start with an empty session and rebooting had no effect on memory usage. kded4 is currently at 818 MB and rising as I am typing this.

I also took a look at the services, and I didn't seem to have any non-essential ones running. Most I didn't think I could safely stop: things like "Keyboard Daemon" and "Network Status". Though I did try to stop BlueDevil since I don't use any bluetooth devices on this system. I also tried to stop "Remote URL Change Notifier" since this computer does not share or access any shared network folders. However I received an error that was unable to stop this service.

Since you mentioned that your kded4 process is holding at a mere 22 MB, I am all the more curious why mine is eating memory like crazy. Is this a bug? Is there something wrong with y system? I have no clue, and searching has not turned up anything more.

Also it is worth noting that I did not run any video conversions or rendering today, so this is happening even during "standard" usage.

Jim,
it's a bug.
you just insert in your search engine of choice "kded4 high cpu" or just "kded4 cpu"
you'll find bugs/reports since 2009 until now and from suse to arch to ubuntu to debian.
this >> http://kdepepo.wordpress.com/2011/05/11 ... ded4-bugs/ explains what is kded4 and why is hard (once hit by this) to debug this kind of issue. you may even be lucky and identify the offending module easily there's hope!

Which seems to describe my problem as relating to the kde power manager, and if you scroll a bit further down, you will find that a fix is available.
Yet when I try to compile the patch, I get a lot of errors.

What I am wondering is if that fix is too old for the latest Mint KDE; maybe I could break things worse than they already are. Plus I would think that Mint 13 KDE should already have that fix included by default, yes?

I am very new to compiling something like that fix and so I'm probably doing something wrong, although I did follow the INSTALL instructions. In any case, disabling power management is not an option. If I can't fix this I may consider switching to Gnome, although I don't really like Gnome.
--Jim

Okay, so I found a supposedly patched version of polkit that was packaged in a .deb, so I instaled it because the source patch would never compile. The problem remained
At that point I realized that I actually needed to do work and couldn't afford to have all my memory being drained.

Confused and at a loss for what to do, I eventually worked-around this problem by installing Gnome; but Gnome was not usable at all, strange bugs and no bottom panel to switch windows, so I then moved to XFCE. I am loving XFCE! Total memory usage even with firefox open while I am typing this is 600 MB... that's less than kded4 by itself!

I should also mention that kded4 is still running in the background it seems, but it now holds at 11.9 MB so whatever was going on appears to be tied to the KDE desktop. If this is a bug as zerozero said, than it is a serious show-stopper. I love KDE, but I can't have my system continually consuming all RAM constantly, especially when I need it for video editing.

At this point, I would like to remove KDE entirely, but there's probably some app I need, and as long as kded4 is in it's cage now thanks to XFCE, I suppose there is no harm in leaving it installed.

I don't really feel I should mark this as solved, because it hasn't been solved, just side-stepped.
--Jim

I don't really feel I should mark this as solved, because it hasn't been solved, just side-stepped.

... And you never tried to fully solve it, either with my suggestions or through the link that was posted. Well, except for a patch you found. If you were going to move to another desktop why wouldn't you at least try every suggestion fully? What would you have to lose even if you borked your KDE install?

Something else that dawned on me thinking about why this happened to you and not everyone else here. Perhaps using your old /home when you upgraded to Mint 13 brought with it a faulty configuration file. Something I mentioned back then when you had questions about doing that.

I don't really feel I should mark this as solved, because it hasn't been solved, just side-stepped.

... And you never tried to fully solve it, either with my suggestions or through the link that was posted. Well, except for a patch you found. If you were going to move to another desktop why wouldn't you at least try every suggestion fully? What would you have to lose even if you borked your KDE install?

Something else that dawned on me thinking about why this happened to you and not everyone else here. Perhaps using your old /home when you upgraded to Mint 13 brought with it a faulty configuration file. Something I mentioned back then when you had questions about doing that.

Anyway, if you're happy, I'm happy.

I think you misunderstood me... I didn't install Mint XFCE edition... I just pulled it from the repos. And I did follow your suggestion, as I mentioned in my earlier post there wasn't really any services I could safely stop. If I stop my keyboard daemon then I can't type... if I stop my network daemon, then I cant access these forums.
Maybe you meant something else that I don't understand. If so, then I apologize -- remember I am still pretty new to this.

That link that zerozero posted, led me to figuring out that it was the power daemon, which as I mentioned in my earlier post, that I can't just disable because I need power management. So I tried for two days to get it patched and fixed, and after wrestling with that, I needed to do work using my computer, and I can't do it with that process eating all of my RAM.

I'm not really sure what else that I -- a new user with no coding skills -- am expected to do. Or why you say that I never tried to solve the problem. I actually think that I went further with it than most people (normal users) would.